1. Field of the Invention
The present invention relates to the mounting structure of a shaft to be tested on a balancer.
2. Description of the Related Art
In a balance test performed on a shaft to be tested such as a propeller shaft or the like, a flexible coupling provided on an end portion of the tested shaft is mounted to a mounting surface plate of the balancer by a plurality of bolts.
In conventional art, a centering shaft provided on a center axis of the mounting surface plate is fitted to a bearing provided on a center axis of the flexible coupling. The flexible coupling is faucet connected to the mounting surface plate by all of a plurality of bolt mounting portions arranged in a plurality of positions in a peripheral direction of the flexible coupling. In particular, the flexible coupling is faucet connected to the mounting surface plate by fitting collars disposed in the respective bolt mounting portions of the flexible coupling to respective faucet recess portions provided in the mounting surface plate, fastened by bolts inserted through the collars to the mounting surface plate.
In the conventional art, since the collars provided in the flexible coupling are fitted to the faucet recess portions of the mounting surface plate in all of a plurality of bolt mounting portions provided at a plurality of positions in the peripheral direction of the flexible coupling, a slant of each of the collars and complications of an elastomer constituting the flexible coupling are easily generated due to any positioning error of the respective collars provided in the flexible coupling, and positioning error of the respective faucet recess portions provided in the mounting surface plate. Therefore, it is difficult to execute stable balancing.